[Progress of researches on symbionts in the management of mosquito-borne infectious diseases]

Mosquitoes are the main vectors of many infectious diseases, including malaria and yellow fever, which seriously threaten human health across the world. In addition to the use of chemical insecticides, genetic control is a new attempt to currently available interventions used for mosquito vector control. In terms of ecological safety, however, symbiotic control as a novel approach has been proposed for mosquito control. Since there are multiple symbiotic microflora inhabiting in a variety of tissues of mosquitoes, including the digestive tract, they may affect the transmission of mosquito-borne infectious diseases through affecting the lifespan, reproductive competence, and vector competence of the host. In this review, the interactions between symbionts in mosquitoes were summarized, and the research progress of mosquito-associated symbionts in the management of mosquitoborne infectious diseases was reviewed.

Retrospective Analysis of 61 Cases of Children Died of Viral Pneumonia

Abstract

Objective To retrospectively analyze the forensic pathological postmortem examination and clinical data of children who died of viral pneumonia in identification of cause of death cases and to discuss the clinical characteristics and pathological features of viral pneumonia in children, in order to provide reference to pathological diagnosis of viral pneumonia in children caused by 2019 novel coronavirus （2019-nCoV） infection. Methods Postmortem examination data from 61 cases of children whose causes of death were identified as viral pneumonia in recent years were collected from the Center of Forensic Identification, Southern Medical University. The gender, age, clinical symptoms and pathological features were comparatively analyzed. Results Among the 61 cases of children who died of viral pneumonia, most were within 2 years old （83.61%）, and a large proportion died within 2 weeks after the onset of the disease （91.80%）. Gross changes in postmortem examination included respiratory mucosal hyperemia, pleural effusion, pulmonary swelling, variegated pulmonary pleura and serosa, as well as focal pulmonary hemorrhage and pulmonary edema. A large proportion of sick children had enlarged mesenteric lymph nodes （83.61%） and thymic dysplasia （21.31%）. Histopathological changes included edema of alveoli and interstitial substance, pneumorrhagia，shedding of alveolar epithelial cells, serous and （or） fibrous exudation in the alveoli, formation of viral inclusions, formation of transparent membranes, infiltration of inflammatory cells that mainly consisted of macrophages and lymphocytes in interstitial substance and alveoli. Viral infections often affected the heart and gastrointestinal tract. Conclusion The clinical symptoms of children with viral pneumonia are difficult to notice, and because the immune systems of children are not fully developed and they have poor immunity, they can easily become severely ill and even die. Analyzing the forensic autopsies and the histopathological characteristics could provide reference for pathological diagnosis of viral pneumonia.

Underwater spatially, spectrally, and temporally resolved optical monitoring of aquatic fauna

A continuous-wave (CW) Scheimpflug underwater multi-spectral lidar system was constructed to monitor aquatic fauna with spatial, spectral, and temporal resolution. Utilizing a 1 W 414 nm diode laser and a detection set-up with a reflective grating, measurements of shrimp pleopod movements at fixed range, and the swimming of small fish trapped in a clear tube were performed in a 5 m ×0.6 m ×0.6 m water tank. The spatial resolution is about 5 mm, the spectral resolution is 10 nm (from 400 nm to 700 nm), and with proper binning of the CCD, a read-out repetition rate up to 150 Hz can be reached. The experimental results demonstrate that the underwater Scheimpflug lidar system has great potential for detailed monitoring of the small aquatic fauna in oceanic environments.

[Cognitive status and its relationship with serum neuropeptide Y in patients with obstructive sleep apnea hypopnea syndrome]

Objective:To analyze the correlation between cognitive function and serum NPY levels in OSAHS patients, and to explore biomarkers for evaluating cognitive function in adult patients with OSAHS. To verify the validity of MoCA in evaluating cognitive function in OSAHS patients.Method:72 patients with OSAHS and 16 healthy controls were included. Subjects were tested for PSG, MoCA, and MMSE; ELISA was used to detect serum NPY levels in subjects. After 14 days, 10 patients in the control group were randomly selected for re-testing of MoCA to detect the internal consistency, test-retest reliability and simultaneous validity of MoCA.Result:The cognitive dysfunction of OSAHS patients was manifested in visual spatial ability, language and attention. Serum NPY levels were negatively correlated with MoCA scores (r=-0.105), and the correlation was not significant. The internal consistency of the MoCA detected by the Cronbach coefficient α is reliable (0.690), and when "directional ability" deleted,the reliability increases (0.705); In addition, both of test-retest reliability (r=0.884, P=0.001) and simultaneous validity (r=0.701,P<0.01) of MoCA were reliable.Conclusion:MoCA in evaluating the cognitive function of adult with OSAHS is reliable, stable and effective, and when "directional ability" deleted,the reliability increases . The cognitive dysfunction of OSAHS patients is manifested in visual spatial ability, language and attention, which is obvious with the disease of severity; serum NPY levels can reflect the severity of OSAHS; there is no significant negative correlation between serum NPY level and MoCA total score. Whether it can be used to evaluate cognitive function in OSAHS patients needs further verification.

Metformin reduces SATB2-mediated osteosarcoma stem cell-like phenotype and tumor growth via inhibition of N-cadherin/NF-kB signaling

OBJECTIVE

To investigate the role of SATB2 in stem cell-like properties of osteosarcoma and identify new strategies to eliminate cancer stem cells of osteosarcoma.

MATERIALS AND METHODS

Osteosarcoma cancer stem cells were derived by sarcosphere generation or chemo drug enrichment. SATB2 and pluripotency-associated gene expression in osteosarcoma CSCs were analyzed using qRT-PCR and Western blotting. The sphere formation assay, cell counting kit-8 assay and anti-chemotherapy proteins were used to measure the effects of altered SATB2, N-cadherin expression or metformin treatment in CSCs. Nude mice were injected with SATB2-deficient U2OS/MTX cells to assess the role of SATB2 in osteosarcoma growth and chemoresistance in vivo. Bioinformatics analyses were performed to identify SATB2 downstream target genes and immunochemistry to determine the correlation between SATB2 expression and patient outcome. Western blotting and luciferase reporter assays were used to examine the effects of N-cadherin and SATB2 inhibition on the NF-kB pathway.

RESULTS

SATB2 was upregulated in osteosarcoma stem cells. Knockdown of SATB2 decreased sarcosphere formation, cell proliferation and stem cell-like gene expression in vitro, meanwhile reduced tumor growth and chemoresistance in vivo. High SATB2 expression in osteosarcoma patient samples was associated with poor clinical outcome. N-cadherin was one critical downstream target gene of SATB2 that mediated the stem cell-like phenotype. Reduction of SATB2 or N-cadherin resulted in NF-kB inactivation, which led to impaired osteosarcoma sphere formation and tumor cell proliferation. Metformin treatment of osteosarcoma cells enhanced the effects of chemotherapy via suppression of N-cadherin.

CONCLUSIONS

SATB2 plays an important role in regulating osteosarcoma stem cell-like properties and tumor growth. The combination of conventional chemotherapy and metformin may be a promising therapeutic strategy for osteosarcoma patients.

Intrinsically patterned two-dimensional materials for selective adsorption of molecules and nanoclusters

Two-dimensional (2D) materials have been studied extensively as monolayers, vertical or lateral heterostructures. To achieve functionalization, monolayers are often patterned using soft lithography and selectively decorated with molecules. Here we demonstrate the growth of a family of 2D materials that are intrinsically patterned. We demonstrate that a monolayer of PtSe₂ can be grown on a Pt substrate in the form of a triangular pattern of alternating 1T and 1H phases. Moreover, we show that, in a monolayer of CuSe grown on a Cu substrate, strain relaxation leads to periodic patterns of triangular nanopores with uniform size. Adsorption of different species at preferred pattern sites is also achieved, demonstrating that these materials can serve as templates for selective self-assembly of molecules or nanoclusters, as well as for the functionalization of the same substrate with two different species.

E2F, HSF2, and miR-26 in thyroid carcinoma: bioinformatic analysis of RNA-sequencing data

In this study, we examined the molecular mechanism of thyroid carcinoma (THCA) using bioinformatics. RNA-sequencing data of THCA (N = 498) and normal thyroid tissue (N = 59) were downloaded from The Cancer Genome Atlas. Next, gene expression levels were calculated using the TCC package and differentially expressed genes (DEGs) were identified using the edgeR package. A co-expression network was constructed using the EBcoexpress package and visualized by Cytoscape, and functional and pathway enrichment of DEGs in the co-expression network was analyzed with DAVID and KOBAS 2.0. Moreover, modules in the co-expression network were identified and annotated using MCODE and BiNGO plugins. Small-molecule drugs were analyzed using the cMAP database, and miRNAs and transcription factors regulating DEGs were identified by WebGestalt. A total of 254 up-regulated and 59 down-regulated DEGs were identified between THCA samples and controls. DEGs enriched in biological process terms were related to cell adhesion, death, and growth and negatively correlated with various small-molecule drugs. The co-expression network of the DEGs consisted of hub genes (ITGA3, TIMP1, KRT19, and SERPINA1) and one module (JUN, FOSB, and EGR1). Furthermore, 5 miRNAs and 5 transcription factors were identified, including E2F, HSF2, and miR-26. miR-26 may participate in THCA by targeting CITED1 and PLA2R1; E2F may participate in THCA by regulating ITGA3, TIMP1, KRT19, EGR1, and JUN; HSF2 may be involved in THCA development by regulating SERPINA1 and FOSB; and small-molecule drugs may have anti-THCA effects. Our results provide novel directions for mechanistic studies and drug design of THCA.

Survey and genetic variation of Spirometra erinaceieuropaei sparganum in frogs and snakes from Guangxi of southern China

The prevalence of sparganum infection in wild frogs (Rana rugulosa and R. temporaria) and snakes (Enhydris chinensis) was investigated in Guangxi Zhuang Autonomous Region of Southern China from June 2013 to August 2013. The results showed that 30.37% (65/214) of the caught wild frogs and 50% (3/6) of examined snakes were found to be infected with plerocercoids (spargana) of the genus Spirometra. To investigate the genetic variation of the collected spargana, three mitochondrial DNA (mtDNA) regions, namely cytochrome c oxidase subunit 1 and 3 (cox1 and cox3), NADH dehydrogenase subunits 4 (nad4) were amplified, sequenced, and analyzed. The sequences of cox1, cox3 and pnad4 are 444, 387 and 585 bp in length, respectively. The base composition of cox1, cox3 and pnad4 were generally AT rich with a mean of 62.7%, 67.2% and 64.9%, respectively. Phylogenetic analyses using Bayesian inference (BI) and maximum parsimony (MP) indicated that all the Spirometra sparganum isolates in Guangxi represented S. erinaceieuropaei.

Improvements on a patient-specific dose estimation system in nuclear medicine examination

The purpose of this paper is to develop a patient-specific dose estimation system in nuclear medicine examination. A dose deposition routine to store the deposited energy of the photons during their flights was embedded in the widely used SimSET Monte Carlo code and a user-friendly interface for reading PET and CT images was developed. Dose calculated on ORNL phantom was used to validate the accuracy of this system. The ratios of S value for (99m)Tc, (18)F and (131)I computed by this system to those obtained with OLINDA for various organs were ranged from 0.93 to 1.18, which were comparable to that obtained from MCNPX2.6 code (0.88-1.22). Our system developed provides opportunity for tumor dose estimation which cannot be known from the MIRD. The radiation dose can provide useful information in the amount of radioisotopes to be administered in radioimmunotherapy.

Non-invasive pulsed cavitational ultrasound for fetal tissue ablation: feasibility study in a fetal sheep model

OBJECTIVES

Currently available fetal intervention techniques rely on invasive procedures that carry inherent risks. A non-invasive technique for fetal intervention could potentially reduce the risk of fetal and obstetric complications. Pulsed cavitational ultrasound therapy (histotripsy) is an ablation technique that mechanically fractionates tissue at the focal region using extracorporeal ultrasound. In this study, we investigated the feasibility of using histotripsy as a non-invasive approach to fetal intervention in a sheep model.

METHODS

The experiments involved 11 gravid sheep at 102-129 days of gestation. Fetal kidney, liver, lung and heart were exposed to ultrasound pulses (< 10 µs) delivered by an external 1-MHz focused ultrasound transducer at a 0.2-1-kHz pulse-repetition rate and 10-16 MPa peak negative pressure. Procedures were monitored and guided by real-time ultrasound imaging. Treated organs were examined by gross and histological inspection for location and degree of tissue injury.

RESULTS

Hyperechoic, cavitating bubble clouds were successfully generated in 19/31 (61%) treatment attempts in 27 fetal organs beneath up to 8 cm of overlying tissue and fetal bones. Histological assessment confirmed lesion locations and sizes corresponding to regions where cavitation was monitored, with no lesions found when cavitation was absent. Inability to generate cavitation was primarily associated with increased depth to target and obstructing structures such as fetal limbs.

CONCLUSION

Extracorporeal histotripsy therapy successfully created targeted lesions in fetal sheep organs without significant damage to overlying structures. With further improvements, histotripsy may evolve into a viable technique for non-invasive fetal intervention procedures.

Vortex phase diagram of the layered superconductor Cu0.03TaS2 for H is parallel to c

The magnetization and anisotropic electrical transport properties have been measured in high quality Cu(0.03)TaS(2) single crystals. A pronounced peak effect has been observed, indicating that high quality and homogeneity are vital to the peak effect. A kink has been observed in the magnetic field, H, dependence of the in-plane resistivity ρ(ab) for H is parallel to c, which corresponds to a transition from activated to diffusive behavior of the vortex liquid phase. In the diffusive regime of the vortex liquid phase, the in-plane resistivity ρ(ab) is proportional to H(0.3), which does not follow the Bardeen-Stephen law for free flux flow. Finally, a simplified vortex phase diagram of Cu(0.03)TaS(2) for H is parallel to c is given.

Prolactin receptor heterogeneity: processing and signalling of the long and short isoforms during development

During development, the fetus is exposed to prolactin activity from the placenta, as well as from the developing fetal pituitary. Distinct prolactin receptor isoforms, having different cytoplasmic domains generated by alternative splicing, are expressed as development proceeds at different levels in different organs. The "long" receptors are able to mediate transduction of all signals examined, in contrast with the "short" isoforms, whose truncated cytoplasmic domains are able to mediate a much smaller repertoire of signals and can act as dominant negatives. Our studies demonstrate that, although these forms share internalization mechanisms, the long form is internalized faster, resulting in more rapid down-regulation of this form. In order to examine the mechanisms by which prolactin may exert trophic effects on its target tissues during development, we have examined the signalling pathways through which prolactin binding to the long receptor regulates the transcription of cyclin D1. Our studies reveal the importance of the JAK/STAT (Janus kinase/signal transduction and activators of transcription) pathway, and the complexity of prolactin signalling to this promoter.

A random coefficient degradation model with random sample size

In testing product reliability, there is often a critical cutoff level that determines whether a specimen is classified as "failed." One consequence is that the number of degradation data collected varies from specimen to specimen. The information of random sample size should be included in the model, and our study shows that it can be influential in estimating model parameters. Two-stage least squares (LS) and maximum modified likelihood (MML) estimation, which both assume fixed sample sizes, are commonly used for estimating parameters in the repeated measurements models typically applied to degradation data. However, the LS estimate is not consistent in the case of random sample sizes. This article derives the likelihood for the random sample size model and suggests using maximum likelihood (ML) for parameter estimation. Our simulation studies show that ML estimates have smaller biases and variances compared to the LS and MML estimates. All estimation methods can be greatly improved if the number of specimens increases from 5 to 10. A data set from a semiconductor application is used to illustrate our methods.

[A study on fractals in the epidemics of measles]

Fractal is a new field of science to study the complexity and irregularity of events. The basic principles of fractal are introduced in this paper and used in the analyses of measles epidemics in Guangdong Province and Nanping district of Fujian Province, based on the monthly reported data on incidence, from 1951 to 1989. The results show that there are fractals in measles epidemics, the fractal dimensions are 1.588 and 1.626 before vaccination, and change to 1.716 and 1.758 after the vaccination respectively, indicating that the epidemics of mealses have become more complex and irregular than before. It is shown that fractal study is useful in expressing the complexity and irregularity of mealses epidemics.

[A case-control study of childhood leukemia]

A 1:1 matched case-control study was conducted to investigate the etiological factors of childhood leukemia. It was found that there were five risk factors: (1) children living in the environmental pollution area, OR (95% CI) = 2.84 (1.14-7.10); (2) exposure to extreme low frequency electronmagnetic field (ELF), OR (95% CI) = 2.01 (1.18-3.42); (3) history of postnatal X-ray exposure, OR (95% CI) = 4.53 (1.68-12.21); (4) history of taking chloramphenicol, OR (95% CI) = 3.60 (1.62-8.01); (5) history of taking, antipyretic or analgesic drugs, OR (95% CI) = 1.93 (1.09-3.42). A protective factor was also discovered. Mothers often eating fish, pork and other meat foods, OR (95% CI) = 0.33 (0.18-0.59). The analysis of the population attributable risk showed that 91% of the childhood leukemia cases might attribute to these five risk factors. The interaction among these etiological factors was estimated. Results showed that there was a positive interaction between the X-ray exposure and chloramphenicol on additive model, the relative excess risk due to interaction (RERI) of childhood leukemia was 3.04.

[Drinking water and leukemia]

A retrospective cohort study was conducted to investigate the relationship between drinking water contamination and risk of leukemia in human being. It was found that the leukemia incidence rate of group D who drank the tap-water from Donghu Lake was significantly higher than that of the groups C and H who drank the tap-water from Changjiang River and Hangjiang River, RR = 1.77, 95% CL = 1.36-2.30, P < 0.01. But the difference between group C and group H is not significant. By using the sex- age-strata analysis; trend and correlation analysis, the results showed that there was a significant positive correlation between the RR of incidence of leukemia and tap-water mutagenicity. It was also connected with pollution of halogenated hydrocarbons in drinking water.

The N-terminal hydrophobic domain of P450c21 is required for membrane insertion and enzyme stability

Microsomal cytochromes P-450 are known to be integrated into smooth endoplasmic reticulum through their hydrophobic sequences located at the N termini. The length requirement of the membrane insertion signal was determined by the generation of six plasmids encoding mutant P450c21 that lacked various portions of the N-terminal hydrophobic domains. When they were transcribed and translated in vitro in the presence of endoplasmic reticulum membranes, mutant protein lacking more than a third of the first hydrophobic domain gradually lost the ability to insert into the membrane and stayed mostly in the soluble fraction when the first N-terminal hydrophobic domain was removed. The steady-state amount of the truncated proteins was progressively reduced in parallel to the extent of their N-terminal deletions, due to their fast degradation. This process was accompanied by a decrease in the enzymatic activity. Therefore, the first hydrophobic domain of P450c21 not only serves as a membrane targeting and anchoring domain, but it is also important for the in vivo protein stability.

[Effect of processing on phospholipid of Dioscorea opposita Thunb]

A study of the chemical changes of phospholipid in crude and seven processed samples of Dioscorea opposita was carried out by molybdenum blue colorimetry and TLCS. The result shows that the total phospholipid content in the sample processed by honey bran comes out the highest (180.31 mg/100g).

[Effect of processing on the extraction of alkaloids from Strychnos]

Results of experiments showed that the contents of strychnine and brucine were about the same in decoction of Strychnos nux-vomica and S. pierriana, but the contents of vomicine, strychnine N-oxide and brucine N-oxide were greater in the former than in the latter. The contents of strychnine and brucine were greater under scalding with hot sand than deep-frying with sesame oil.

Paroxysmal nocturnal hemoglobinuria: report of one case

Paroxysmal nocturnal hemoglobinuria (PNH) is a complex stem cell disorder and its occurrence in childhood is quite uncommon. A 6-year-old girl with pancytopenia was presented. There is no nocturnal hemoglobinuria or other symptoms of chronic hemolysis. Bone marrow examination revealed mild hypocellularity initially, and a tentative diagnosis of aplastic anemia was made. This patient received conventional therapy with uneventful course. Two consecutive episodes of hemolytic transfusion reaction were noted and positive sugar water test and Ham,s test lead the clue of PNH. The literature on the clinical manifestation, pathogenesis, diagnosis and management of PNH is reviewed briefly.

Efficacy of a mass hepatitis B vaccination program in Taiwan. Studies on 3464 infants of hepatitis B surface antigen-carrier mothers

To evaluate the efficacy of the mass hepatitis B vaccination program in Taiwan in interrupting perinatal hepatitis B virus transmission, 3464 randomly selected 18-month-old infant vaccinees born to hepatitis B surface antigen-carrier mothers were recruited from 9697 eligible infants during a six-month period of the program. They were divided into ten groups according to maternal infectivity and compliance with the vaccination schedule. Serum samples were tested for hepatitis B surface antigen, antibody to hepatitis B surface antigen, and antibody to hepatitis B core antigen. In 786 infants who had highly infectious mothers and who received hepatitis B immune globulin and vaccine on schedule, the protective efficacy was about 85%. The efficacy seemed to be slightly lower in those immunized off schedule. Overall, 11% of infants still carried hepatitis B surface antigen, and 81% of the infants had antibody to hepatitis B surface antigen that exceeded 10 mIU/mL in more than 90% of them. The geometric mean titers of antibody to hepatitis B surface antigen were more than 200 mIU/mL in every group of infants. We conclude that the mass vaccination program is efficacious in preventing perinatal hepatitis B virus transmission and the chronic carrier state; most infant vaccinees have adequate levels of protective antibody at 18 months of age. This program is extremely significant in the control of hepatitis B virus infection in Taiwan.

Characterization of hepatitis B e antigen from human breast milk

Hepatitis B e antigen (HBeAg) but not surface antigen (HBsAg) was detected in 20% of the milk samples taken from HBsAg carrier mothers by radioimmunoassay. The density of milk e antigen particles was peaked at 1.32 g/ml in CsCl gradient ultracentrifugation. HBeAg was found in 1.33 M and 3.24 M (NH4) 2SO4 precipitates from breast milk but neither of HBeAg in both precipitates showed exactly identical with serum-derived e antigen. Five bands of polypeptides with molecular weight of 8,000, 21,500, 37,000, 53,000 and 68,000 daltons were seen after polyacrylamide gel electrophoresis from the milk e antigen. In addition, the IgA was shown significantly high in HBeAg positive milk.